The contrast ratio in display applications is the ratio of luminance between the brightest white and the darkest black that can be produced by a display system. It is a major determinant of the image quality of the display system. If a displayed image has a high contrast ratio, a viewer will judge it to be sharper than a displayed image with a lower contrast ratio even if the displayed image with a lower contrast has a higher measurable resolution.
The perceived contrast ratio of a displayed image on a screen illuminated from the viewer side using a (front) projector, however, is also dependent from the environment in which the projector is operated and the image is projected. As an example in a conference room, the projected images on the screen appear washed out when the lights in the conference room are turned on. When all lights in the conference room are turned off, the projected images on the screen appear to be more crystal-clear. This effect is due to the reflection of the ambient light into the viewers' eyes by the screen, which in turn, reduces the perceived contrast ratio, even though the projector has a high contrast ratio.
Therefore, what is desired is a method for reducing the reflection of the ambient light by the screen onto the viewers' eyes.